<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
  <!--函数的使用-->
  function max(a,b){
    if (a>b){
      return a;
    }else {
      return b;
    }
  }
  //调用函数
  let i =max(4,5);
  window.alert(i);
  let max1 = max(4,9,5);
  alert(max1);
</script>
</body>
</html>